According to a conventional stencil plate making printing machine, a stencil master plate is processed by a plate making printing unit consisting of a thermal head and a platen roller according to an original image signal obtained by a plate making reading unit, and the processed stencil master plate is wrapped around a printing drum. To obtain a printed copy, the ink which has been pushed out from the printing drum and passed through the perforations corresponding to a desired picture image is transferred onto printing paper.
In such stencil master plate printing devices, it is sometimes required to have a function of so-called multiple frame copying which allows picture images of, for instance, two B5 sized originals to be written into a duplication medium having a B4 sized printing region, side by side.
Such a multiple frame printing function can be accomplished according to the following control process.
First of all, after a multiple frame printing key is pressed, a first original which is to be copied as part of the multiple frame printing process is read at a plate making reading unit and the image of this original is written into a stencil master plate in a plate making printing unit consisting of a thermal head and a platen roller. When it is detected that the reading of the first original at the plate making reading unit is completed, the rotation of the platen roller is stopped, and the writing process by the thermal head is temporarily interrupted.
When reading of a second original is started, the printing process by the thermal head is started so that a stencil master plate may be processed with the originals allocated to a plurality of frames, and the stencil master plate is then wrapped around a drum to start the process of printing.